The present invention relates to sun visors for vehicles. Aspects of the invention relate to a sun visor construction which is mounted to provide lift as a result of air flow passing over the forward and reverse sides of the sun visor.
Sun visors of various constructions are known for shielding the passage of sunlight through an upper portion of the windshield of a vehicle.
However, known sun visors often have a rear surface which causes a substantial amount of turbulence as air passes over the front and rear surfaces of the sun visor during vehicle travel. This turbulence can add to the drag generated by the sun visor.
In addition, known sun visors have been mounted to vehicles in a manner where they significantly add to the drag produced by the sun visor as a result of air passing along the sun visor surfaces in comparison to the drag if the sun visors were mounted in a different orientation.
With the cost of fuel in today""s economy, very small percentage improvements in the drag generated by a sun visor on a truck or other vehicle travelling at highway speeds (e.g., 55 miles per hour to 65 miles per hour) can result in significant savings over the operating life of the vehicle. These savings are particularly apparent in connection with trucks, which can be operated for hundreds of thousands of miles, and in many cases in excess of a million miles, during their life.
In addition, sun visors with lamps or marker lights included therein may have exposed wiring or lamps at the rear of the sun visor, which can decrease the aerodynamic efficiency of the sun visor.
Moreover, sun visors may be of relatively complex and difficult to manufacture shapes.
The present invention is directed toward sun visors with novel and non-obvious characteristics as set forth in the claims below. These sun visors may solve one or more of the disadvantages of the prior art, but the invention is not limited to the specific embodiments shown herein nor to sun visors with all or specific subcombinations of features. That is, the invention is directed toward novel and non-obvious sun visor aspects both alone and in various combinations and subcombinations with one another.
In accordance with one aspect of an embodiment, an elongated sun visor is provided for mounting to a vehicle in a position to shield a portion of an upwardly extending windshield of the vehicle from overhead sunlight. The vehicle typically comprises an upright vehicle front section, having a vehicle front surface section extending upwardly above the windshield. Desirably, the vehicle front surface section substantially follows the contour of the upwardly extending windshield at least for a distance above the windshield. This vehicle front surface section may be formed by a portion of the vehicle roof, such as in a raised roof truck configuration, by a fairing mounted to the vehicle roof, or in any other convenient manner. Typically, at least one sun visor support is provided for coupling the sun visor to the vehicle to support the sun visor. The sun visor support is desirably coupled to at least the upright vehicle front section.
The sun visor may comprise an elongated sun visor front having a length and comprising top and bottom edge portions. The sun visor front in one form comprises a first major front surface and a second major back surface. Desirably, when the sun visor is mounted to the vehicle, the sun visor first major surface is substantially parallel to the vehicle front surface section. Plural marker or other lights may be coupled to the sun visor front so as to be visible from the front of the vehicle when the lights are operated. An elongated sun visor back desirably extends at least along a major portion of the second major back surface of the sun visor front. The sun visor back may comprise a lower back portion which together with a lower portion of the sun visor front in this embodiment defines an elongated enlarged lower sun visor section. This enlarged lower section may define at least one elongated wiring receiving passage for receiving electrical wiring for the lights. In addition, the passage may be sized to accommodate rear surfaces of lamps mounted to the sun visor front. The forward surfaces of the lamps, or lenses attached to the lamps, may be substantially flush with the first major front surface of the sun visor front. The sun visor back may also comprise a transition back portion which extends upwardly from the lower back portion and converges toward the major back surface of the sun visor front. A sun visor back may extend upwardly to the top edge portion of the sun visor front but more desirably comprises an upper edge portion which terminates below the sun visor top edge portion and generally above the lights.
The sun visor back in one embodiment may comprise at least one back section which is a separate piece from the sun visor front and which is coupled to the sun visor front to complete the sun visor construction. The sun visor back may alternatively, in this embodiment, be comprised of plural back sections. At a location intermediate the length of the sun visor back, such as at the center of the sun visor, the plural back sections may engage one another. For example, an inner end portion of one sun visor back section may overlap an inner end portion of another sun visor back section. One of the inner end portions may define a recessed shelf which is overlapped by the other of the inner end portions.
As another aspect of an embodiment, the sun visor may have an average distance or height d between the top and bottom edge portions of the sun visor front. In addition, the vehicle front surface section desirably substantially follows the contour of the windshield for a distance equal to at least d beyond the portion of the vehicle front section intersected by a projection of the sun visor top edge portion on to the vehicle front section in a direction normal to the contour followed by the vehicle front surface section. For example, a best fit line for a location on the front surface section may be found by, for example, averaging a plurality of points along a vertical section of the vehicle front surface. A projection of the sun visor top edge portion may be taken along a line perpendicular to this best fit line and onto the vehicle front surface to determine the intersection of the projection of the sun visor top edge portion with the vehicle front surface section.
In addition, in an aspect of an embodiment, a vertical section may be taken through the sun visor and the front vehicle section. The contour followed by this vertical section of the vehicle front surface may be approximated such as a best fit or first line. A first distance A may be defined to be the length of the shortest line normal to the first lines and the average back surface contour along the vertical section at any location which is no greater than 75 percent of the distance d from the bottom edge portion of the sun visor front. By average back surface contour, it is meant the contour of the back surface of the sun visor back excluding abrupt projections and projections designed to accommodate lights recessed into the front of the sun visor. Desirably any such abrupt projections and light accommodating projections have curved surfaces to minimize turbulence. In addition, a second distance C may be defined to be the length of the shortest line normal to the first line and the average major back surface contour of the sun visor front along the vertical section at any location greater than 75 percent along the distance d from the bottom edge portion of the sun visor front. In one specific embodiment, the distance C is no greater than the distance A . Desirably, the distance C is equal to at least 0.54A and more desirably the distance C ranges from about 0.6A to about 0.8A. Based on two dimensional computer modeling, a particularly desirable configuration is where the distance C is equal to 0.76A.
A particularly desirable configuration of sun visor is one in which the back comprises a back surface which is configured to provide positive lift, acting in a direction approximately normal to the back surface of the sun visor, in response to air flow passing along the sun visor front and sun visor back as the vehicle travels in a forward direction at least at selected speeds (for example, at highway speeds of 55-65 miles per hour).
As a further aspect of an embodiment, the top edge portion of the sun visor front may curve inwardly toward the vehicle front surface section.
In addition, in a desirable embodiment, the sun visor is comprised of a sun visor front and a sun visor back and wherein the sun visor back terminates below the top edge portion of the sun visor front member.
Desirably, in accordance with certain embodiments, the sun visor may have a transition back portion which, together with any exposed portion of the major back surface of the sun visor front located above the transition back portion, is generally arched in vertical section. More desirably, these surfaces are configured to be generally concave in vertical section relative to the vehicle front surface section.
As another aspect of an embodiment, a transition back portion comprises an upper edge portion and is designed such that at least a major portion of the upper edge portion is coupled to or intersects the major back surface of the sun visor front at a location which is at least one-half of the distance between the sun visor front top and bottom edge portions as measured from the bottom edge portion. More desirably, at least a major portion of the upper edge portion is coupled to or intersects the major back surface of the sun visor front at a location which is at least one-third of the distance between the sun visor front top and bottom edge portions as measured from the top edge portion of the sun visor front. In a particularly desirable embodiment, at least a major portion of the upper edge portion of the transition back portion is coupled to or intersects the major back surface of the sun visor front at a location between one-half and one-fourth of the distance between the sun visor front top and bottom edge portions as measured from the top edge portion of the sun visor front. As another aspect of an embodiment, the transition back portion terminates at such location.
In certain embodiments of a sun visor, the back surface of the sun visor is desirably curved without abrupt angled transitions. The sun visor may be of unitary one-piece construction. However, more desirably the sun visor is comprised of a sun visor front member with bottom and top edge portions and a sun visor back which is coupled to the sun visor front member. The sun visor back comprises a first major surface portion which is oriented to face the back surface of the front member. In addition, the sun visor back has at least a major portion of a second surface which is oriented toward and generally faces a front section of the vehicle when the sun visor is mounted to the vehicle. The sun visor front member and sun visor back may together define at least one elongated marker light wiring receiving passage extending along at least a major portion of the length of the sun visor. One or more pockets may also be defined to accommodate lights mounted to the sun visor front member and which are recessed into the sun visor. The sun visor back may, in one form, comprise at least two sun visor back sections. Inner end portions of such sun visor back sections may each define a portion of a support bracket receiving opening. Desirably, the second or back surface of the sun visor back and the sun visor front member are configured so as to provide lift acting in a direction approximately normal to the back of the sun visor when the vehicle travels forward. This lift results from air flow past the exposed surfaces of the sun visor front member and sun visor back when the sun visor is mounted to the vehicle and the vehicle is moving forwardly at least at selected speeds.
In a particularly desirable embodiment, a sun visor comprises a sun visor body with a front and back with the back facing and being spaced from the vehicle roof section. The back may comprise rear surface defining means configured and positioned relative to a section of the vehicle roof so as to create a positive lift in a direction approximately normal to the back surface as air flows past the front and back of the sun visor when the vehicle travels forward at least at certain speeds.
Again, the present invention is not limited to the specific embodiments described herein, but encompasses novel and non-obvious aspects of sun visors, alone and in various combinations with one another, as set forth in the claims below.